Replaced metal halide bulb..now what?

[yoki32]

I just replaced my metal halide bulb on my fixture. It was 1 year old and I found the intensity not that great anymore. Now how long should I use an egg crate cover to protect my lps/sps corals from getting a shock from the new light? 1 month around is that good?

 

[tkeracer619]

Depends on the bulb/ballast combination. Egg crate is actually called light diffuser and blocks a ton of light from entering the tank. I wouldn't use it long. I'd raise the lights or use a screen.

I don't let my bulbs go beyond where I can just swap them. For a 250w radium 20k with m80 ballast that is 16 months. Ebay bulbs are about 6 months if that.